With the development of the economy, China's demand for oil and gas resources has also increased. However, due to the fact that most of the early main oil fields have entered the middle and late stages of development and the crude oil production has not been able to make a major breakthrough, China's oil and gas dependence has reached a record high in recent years. Therefore, China's oil and gas exploration and development are gradually focusing on the complex formations that have not drawn much attention in the early days, such as fractured formations. At present, the fractured reservoirs drilled in China are gradually increasing. The explored geological reserves of fractured oil and gas reservoirs account for 28% of the total explored reserves in the country, and the oil and gas production of fractured reservoirs has exceeded 14 million tons per year. In the future, the oil and gas production of fractured reservoirs will play an increasingly important role in the development of China's petroleum industry.
The fractured formation has a characteristic of pressure sensitivity; the safety drilling pressure window is very narrow, and some fractured reservoirs do not even have a safety pressure window. Under the above circumstances, gas kick is highly prone to occur during a drilling process. Therefore, the problem of well control runs through the entire drilling process of the fractured formation. Once improperly handled, serious accidents such as kicks or blowouts may occur. At present, the methods of treating gas kick are mainly conventional well killing methods such as driller's and engineer's methods. For the gas kick during a drilling process of fractured reservoirs without a safety pressure window, if these conventional well killing methods are used, it is easy to cause the leakage and the concurrence of leakage and blowout. Not only will it not effectively resolve the problem of gas kick or blowout, it may even destroy the reservoir and affect the efficiency of oil and gas resource exploration.